Flash Flood Watch 8, NWS Lincoln, IL

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LINCOLN IL
1252 PM CDT TUE JUN 25 2013

.DISCUSSION...
ISSUED 1045 AM CDT TUE JUN 25 2013

MADE MINOR ADJUSTMENTS TO THE FORECAST TO INCREASE AFTERNOON POPS SLIGHTLY
IN MUCH OF CENTRAL AND EASTERN IL. THE ILX 12Z SOUNDING INDICATED
PLENTY OF INSTABILITY AVAILABLE...CAPES OVER 4000 IF WE CAN BREAK
OUT OF THE CLOUDS AND SEE MORE SUN. HOWEVER...THE LATEST VISIBLE
SATELLITE LOOP SHOWS UPSTREAM CLOUDINESS IN STORE FOR CENTRAL AND
EASTERN IL THIS AFTERNOON...WITH A FEW BREAKS AND THIN SPOTS AT TIMES.

THE MAIN TRIGGER MECHANISM IS EXPECTED TO BE SHORTWAVE ENERGY/MCV
REMNANTS FROM NW MISSOURI. MANY OF THE SHORT RANGES MODELS
INDICATE THIS WILL IMPACT OUR AREA LATE IN THE AFTERNOON AND
ESPECIALLY TOWARD THE EVENING HOURS. WIND SHEAR IS NOT TOO
IMPRESSIVE NOW...BUT SHORT RANGE MODELS LIKE THE NAM AND LOCAL WRF
INDICATE THAT IT SHOULD INCREASE BY EVENING IN CENTRAL IL WITH
CAPES AROUND 2500 OR SO. SOME CAPPING MAY BE PRESENT IN ECENT AND
SE IL...SO CONVECTION MAY HOLD OFF THERE UNTIL LATER THIS EVENING.

&&

.AVIATION...
ISSUED 1252 PM CDT TUE JUN 25 2013

PERIODS OF THUNDERSTORMS ARE EXPECTED AT ALL OF THE TAF SITES IN
CENTRAL AND EASTERN IL THE NEXT 24 HOURS. THE HIGH RESOLUTION
MODELS LIKE THE HRRR...RUC AND LOCAL WRF ARE IN FAIR AGREEMENT
THAT AT LEAST SCT CONVECTION WILL DEVELOP LATER THIS AFTERNOON IN
WEST CENTRAL IL...IN RESPONSE TO ABUNDANT INSTABILITY AND A
SHORTWAVE NOW MOVING TOWARD CENTRAL MO...AND IMPACT THE TAF SITES
AROUND 21-23Z.

AM ANTICIPATING A BRIEF RESPITE IN THE CONVECTION AS THE
ATMOSPHERE LIKELY STABILIZES...DUE TO RAIN FROM LATER AFTERNOON
STORMS...AROUND OR SHORTLY AFTER SUNSET.

LATER IN THE EVENING AND OVERNIGHT...THE SHORT RANGE AND HIGH
RESOLUTION MODELS ARE IN FAIR AGREEMENT THAT SCT CONVECTION WILL
REDEVELOP CLOSE TO OR SHORTLY AFTER MIDNIGHT IN RESPONSE TO AMPLE
LOW LEVEL MOISTURE AND INCREASING LOW LEVEL WINDS/MOISTURE
TRANSPORT. AT THIS TIME IT APPEARS THAT THE MOST LIKELY AREA TO
EXPERIENCE THIS WILL BE IN THE NORTHERN TAF SITES FROM KPIA-KBMI.
AM CONFIDENT THIS WILL IMPACT THESE AREAS...SO WENT WITH A
PREDOMINANT TSRA GROUP FOR A FEW HOURS BEFORE DAYBREAK. CONFIDENCE
WANES WITH SOUTHWARD AND EASTWARD EXTENT AS THE MODELS DO NOT
AGREE ON THE PROPAGATION OF THE STORMS.

MILLER
&&

.PREV DISCUSSION...
ISSUED 240 AM CDT TUE JUN 25 2013

SHORT TERM...TODAY THROUGH WEDNESDAY...

MAIN CONCERNS IN THIS PERIOD ARE WITH SEVERE WEATHER POTENTIAL...
ESPECIALLY ON WEDNESDAY.

DAY1 CONVECTIVE OUTLOOK SHOWS THE SLIGHT RISK FROM ABOUT I-72
NORTHWARD TODAY. LATEST IN THE SERIES OF NOCTURNAL MCS SYSTEMS WAS
TRACKING ALONG THE ILLINOIS/WISCONSIN BORDER AT 2 AM. WHILE HIGHER
RESOLUTION MODEL GUIDANCE KEEPS THE TRACK OF THIS WELL TO OUR
NORTH...RADAR MOSAICS STARTING TO SHOW THE OUTFLOW BOUNDARY
DROPPING SOUTHWARD THROUGH NORTHERN ILLINOIS. THE AIR TO THE SOUTH
WILL BECOME QUITE UNSTABLE LATER TODAY WITH CAPES OF OVER 3000
J/KG. ANOTHER MCS PROGGED TO DEVELOP TO THE NORTHWEST AS A
SHORTWAVE MOVES IN FROM THE PLAINS...WITH THIS MCS SLIDING ACROSS
THE NORTH HALF OF ILLINOIS LATER TODAY. HIGHER PROBABILITIES ARE
FOCUSED MORE ON THE I-80 CORRIDOR. STORMS THAT DO FORM WILL AGAIN
HAVE THE POTENTIAL FOR HEAVY RAIN...WITH PRECIPITABLE WATER VALUES
OF AROUND 1.8 INCHES.

SPC PROBABILITY GRAPHICS FOR THE DAY2 OUTLOOK SHOW A SEVERE
WEATHER THREAT OVER ALL OF OUR AREA BUT FOCUS ON LOCATIONS ALONG
AND EAST OF I-57 WITH THE HIGHEST THREAT FOR SEVERE WEATHER ON
WEDNESDAY...INCLUDING VERY LARGE HAIL AND DAMAGING WINDS. COLD
FRONT SHOULD BE CROSSING THE STATE DURING THE AFTERNOON. AIR MASS
WILL BE EXTREMELY UNSTABLE AHEAD OF IT...WITH CAPES OF AROUND
4500 J/KG AND 0-6KM BULK SHEAR OF 30-40 KNOTS. PRECIPITABLE WATER
VALUES OF AROUND 1.8 INCHES POINT TO POTENTIAL FOR HEAVY RAIN ONCE
AGAIN...BUT HOPEFULLY THE STORMS ON WEDNESDAY WILL BE MORE
PROGRESSIVE AS COMPARED TO THE LAST FEW DAYS.

HIGH TEMPERATURE FORECASTS THE LAST FEW DAYS HAVE BEEN A REAL
STRUGGLE WITH ALL OF THE CONVECTION IN THE AREA. HAVE SCALED BACK
HIGHS A COUPLE DEGREES...GOING CLOSER TO A MET/MAV BLEND. IF THE
CONVECTION TODAY IS MORE ISOLATED...THEN THE WARMER MAV NUMBERS
SHOULD BE ATTAINABLE.

LONG TERM...THURSDAY THROUGH MONDAY...

INITIAL COLD FRONT ON WEDNESDAY WILL BE A BIT OF A TEASE...WITH
VERY WARM AND HUMID CONDITIONS CONTINUING INTO THURSDAY. A STEADY
PUSH OF COOLER AIR SHOULD BEGIN TO SPREAD IN ON FRIDAY AS AN UPPER
LOW OVERSPREADS THE GREAT LAKES...AND STARTS A PERSISTENT
NORTHWEST FLOW OVER THE MIDWEST. BOTH THE GFS AND ECMWF MODELS
SHOW A SIGNIFICANT UPPER TROUGH BEING CARVED OUT OVER THE MIDWEST
AND LOWER MISSISSIPPI VALLEY THIS WEEKEND...WITH THE LATTER MODEL
A BIT MORE PERSISTENT AND LASTING THROUGH EARLY NEXT WEEK.
TEMPERATURES WILL BE SEVERAL DEGREES BELOW NORMAL...BUT NOT
ABNORMALLY OUT OF LINE FOR THE END OF JUNE.

BLENDED MODEL GUIDANCE SHOWS SLIGHT CHANCE POPS FOR MUCH OF THE
FRIDAY THROUGH MONDAY PERIOD. WITH THE COLDER AIR ALOFT AND THE
DEEP TROUGH OVERHEAD...AM RELUCTANT TO COMPLETELY REMOVE RAIN
CHANCES...ALTHOUGH THEY WOULD BE MORE DIURNAL IN NATURE.

GEELHART

&&

.ILX WATCHES/WARNINGS/ADVISORIES...
NONE.
&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LINCOLN IL
1140 AM CDT TUE JUN 25 2013

ILZ027>031-036-037-040-041-047-049-050-261100-
CASS-FULTON-KNOX-MARSHALL-MASON-MORGAN-PEORIA-SCHUYLER-SCOTT-
STARK-TAZEWELL-WOODFORD-
1140 AM CDT TUE JUN 25 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
ILLINOIS.

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED THUNDERSTORMS WILL ONCE AGAIN OCCUR OVER PARTS OF
CENTRAL ILLINOIS. A FEW OF THE MORE INTENSE STORMS WILL BE CAPABLE
OF PRODUCING DAMAGING WIND GUSTS...LARGE HAIL...HEAVY RAINFALL AND
FREQUENT CLOUD TO GROUND LIGHTNING. ADDITIONAL STRONG THUNDERSTORMS
WITH GUSTY WINDS AND HEAVY RAIN ARE ANTICPATED LATER TONIGHT.

FOR INTERESTS ALONG THE ILLINOIS RIVER...FLOODING WILL CONTINUE
DOWNSTREAM OF PEORIA FOR THE NEXT SEVERAL DAYS. ALONG THE SPOON RIVER...
MINOR FLOODING IS EXPECTED TO DEVELOP AROUND LONDON MILLS WEDNESDAY
THROUGH FRIDAY.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

A STRONG COLD FRONT IS SLATED TO MOVE INTO THE REGION LATER ON
WEDNESDAY BRINGING THE THREAT FOR MORE STRONG TO SEVERE
THUNDERSTORMS. THE PRIMARY TIME FRAME LOOKS TO BE IN THE AFTERNOON
AND EARLY EVENING HOURS...WITH DAMAGING WIND GUSTS AND LARGE HAIL
THE PRIMARY THREATS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED LATER THIS AFTERNOON INTO THIS
EVENING. CURRENT INDICATIONS SUGGEST THE TIME FRAME FOR ACTIVATION
WILL BE FROM 3 PM UNTIL 9 PM.

ILZ038-042>046-048-051>057-061>063-066>068-261100-
CHAMPAIGN-CHRISTIAN-CLARK-COLES-CRAWFORD-CUMBERLAND-DE WITT-
DOUGLAS-EDGAR-EFFINGHAM-JASPER-LOGAN-MACON-MCLEAN-MENARD-MOULTRIE-
PIATT-SANGAMON-SHELBY-VERMILION-
1140 AM CDT TUE JUN 25 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL
ILLINOIS...EAST CENTRAL ILLINOIS AND SOUTHEAST ILLINOIS.

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED THUNDERSTORMS WILL ONCE AGAIN OCCUR OVER PARTS OF
CENTRAL THROUGH EAST CENTRAL ILLINOIS. A FEW OF THE MORE INTENSE
STORMS WILL BE CAPABLE OF PRODUCING DAMAGING WIND GUSTS...LARGE
HAIL...HEAVY RAINFALL AND FREQUENT CLOUD TO GROUND LIGHTNING.
ADDITIONAL STRONG THUNDERSTORMS WITH GUSTY WINDS AND HEAVY RAIN
ARE ANTICPATED VERY LATE TONIGHT.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

A STRONG COLD FRONT IS SLATED TO MOVE INTO THE REGION LATER ON
WEDNESDAY BRINGING THE THREAT FOR MORE STRONG TO SEVERE
THUNDERSTORMS. THE PRIMARY TIME FRAME LOOKS TO BE IN THE AFTERNOON
AND EARLY EVENING HOURS...WITH DAMAGING WIND GUSTS AND LARGE HAIL
THE PRIMARY THREATS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED THIS EVENING. CURRENT INDICATIONS
SUGGEST THE TIME FRAME FOR ACTIVATION WILL BE FROM 5 PM UNTIL 11 PM.

ILZ071>073-261100-
CLAY-LAWRENCE-RICHLAND-
1140 AM CDT TUE JUN 25 2013

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST
ILLINOIS.

.DAY ONE...THIS AFTERNOON AND TONIGHT

ISOLATED THUNDERSTORMS WILL BE POSSIBLE TOWARD EVENING AND OVERNIGHT.
SOME OF THE STORMS MAY BE CAPABLE OF PRODUCING GUSTY WINDS...SMALL
HAIL...TORRENTIAL RAINFALL ALONG WITH FREQUENT CLOUD TO GROUND
LIGHTNING.

FLOODING WILL CONTINUE ALONG THE LITTLE WABASH BASIN FOR THE NEXT
SEVERAL DAYS.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

A STRONG COLD FRONT IS SLATED TO MOVE INTO THE REGION WEDNESDAY
NIGHT WITH THE THREAT FOR MORE THUNDERSTORMS. SOME OF THE STORMS
COULD BE SEVERE WEDNESDAY AFTERNOON INTO THE EVENING HOURS WITH
LARGE HAIL AND DAMAGING WIND GUSTS THE PRIMARY THREATS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.

MILLER

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE LINCOLN IL
1032 AM CDT TUE JUN 25 2013

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0525 PM     HAIL             WILLIAMSVILLE           39.95N 89.56W
06/24/2013  M1.00 INCH       SANGAMON           IL   TRAINED SPOTTER

            DELAYED REPORT. TIME ESTIMATED BASED ON RADAR. NICKEL TO
            QUARTER SIZE HAIL. LASTED FOR 5 TO 10 MINUTES.

&&

SHIMON